Digitizing the night sky … inside the UW’s planetarium

It’s a quiet, sunny summer afternoon at the University of Washington’s physics-astronomy complex. But inside the hushed, empty auditorium building, Jake VanderPlas has turned off the lights and shut us inside the recently renovated planetarium.

Jake’s a friend and a fellow UW grad student (a 5th-year Ph.D. candidate in astronomy) who studies, among other cool things, the underlying structure of the universe. Today, though, he’s showing off the nifty digital upgrades that make the formerly old-school projector room a showcase of how to reach out to the public using off-the-shelf computing technology.

The opto-mechanical Minolta projector that still takes up a big chunk of the round, carpeted dome of a room is basically a fancy device for splaying the ceiling with the white dots familiar to generations of school kids on field trips.

But in the early 2000s, a group of grad students invested in a set of 640 by 480 projectors to supplement the old Minolta, adding the ability to place images on the wall.

The old Minolta

Then two years ago, grad student Phil Rosenfield and UW Prof. Andrew Connolly helped to secure a $20,000 grant from Microsoft to help the planetarium go fully digital; free labor and other support helped to help keep the total conversion to about $40,000. A brand-new planetarium would have run in the hundreds of thousands of dollars, VanderPlas says.

With six desktop computers tied to six projectors that run Microsoft Research’s Worldwide Telescope software (which is free for the public to download), a seventh desktop is run by an Xbox controller that allows guides such as VanderPlas to zoom in and out of our solar system, and to scroll across the universe (or at least as much of the known universe as possible). The half-a-dozen projected images are stitched together on the ceiling for a “wow!” effect that’s invaluable, VanderPlas says, for learning.

“The new wave of digital planetariums allows students to experience the universe interactively in ways that haven’t been possible before,” he says. “The sort of immersion that, in the past, was only possible with a pre-rendered movie can now be controlled in real time.”

“Star bulbs” that showed off the constellations were cool — but seeing images such as Hubble’s “deep space field” or the Horsehead Nebula on a small movie screen over your head is even cooler, especially when that image is 8-million pixels strong.

VanderPlas adds that the UW’s digitized space, which was opened earlier this year, can serve as a role model for other university planetariums.

One of the six new digital projectors

“It allows people to really experience these kinds of things,” VanderPlas says, gesturing toward an image of earth plastered vividly to the roof, providing a bit of perspective on just how big the universe really is, and just how tiny our little corner of it.

“There’s something amazing about sitting on a mountain and seeing the swath of the Milky Way across the sky,” he says. This may not be a mountain, but it’s the next best thing.